Problem: Is ${14550}$ divisible by $4$ ?
A number is divisible by $4$ if the last two digits are divisible by $4$ . [ Why? We can rewrite the number as a multiple of $100$ plus the last two digits: $ \gray{145} {50} = \gray{145} \gray{00} + {50} $ Because $14500$ is a multiple of $100$ , it is also a multiple of $4$ So as long as the value of the last two digits, ${50}$ , is divisible by $4$ , the original number must also be divisible by $4$ Is the value of the last two digits, $50$ , divisible by $4$ No, $50$ is not divisible by $4$, so $14550$ is also not divisible by $4$.